Potential Psychoactive Indole Derivatives II: Synthesis of 5-Alkoxyindolines via Reduction of 5-Alkoxy-2-indolinones

As part of a continuing program to define further the role of the indole nitrogen in influencing activity of psychoactive compounds, a series of 5-alkoxy-3-alkylamino-1,3-dimethyl-2-indolinones and indolines were prepared for central activity studies. The intermediate substituted 2-indolinones were prepared by C-5 alkylation of 5-hydroxy-1,3-dimethyl-2-indolinone followed by C-3 alkylation with appropriately substituted chloroalkylamines. The substituted 2-indolinones were then reduced to the indoline derivatives with lithium borohydride. IR and NMR spectroscopy were utilized for the structural characterization of the synthesized compounds.